1. Field of the invention
The present invention relates to an oil seal assembly, particularly, to an oil seal assembly used for sealing an annular cavity formed between the inner and outer rings of a rolling bearing assembly, and interposed between the inner and outer rings of a rolling bearing assembly, particularly which are separable from each other.
2. Description of the Prior Art
There is a known oil seal assembly of this type, which is shown in FIG. 3. As shown in FIG. 3, the oil seal assembly is interposed between the inner ring (5) and outer ring (2) of a rolling bearing assembly (partially shown), which rotatably supports an axle (1), in order to separate an annular cavity (X) in the bearing from the environment (Y). (The rolling bearings used for an automotive wheel hub application are generally angular contact ball bearings or tapered roller bearings, of which inner and outer rings are separable from each other.) The oil seal assembly comprises an outer annular member (4) fitted onto the inner peripheral surface end portion of the outer ring (2) of the bearing assembly and having a single annular seal lip (3) on its inner peripheral surface and an inner annular member (6) fitted onto the outer peripheral surface end portion of the inner ring (5) of the bearing assembly and being in elastic-contact with the annular seal lip (3).
The outer annular member (4) comprises a cylindrical portion (4A) fixed onto the end portion of the inner peripheral surface of the outer ring (2), an annular flange portion (4B) extending from the outer end of the cylindrical portion radially inwardly, and a projecting portion (4C) projecting from the inner edge of the flange portion (4B) obliquely inwardly in the bearing axial direction. The annular seal lip (3) is bonded to the projecting portion (4C). The inner annular member (6) comprises a cylindrical portion (6A) fixed onto the end portion of the outer peripheral portion of the inner ring (5) and an annular flange portion (6B) extending from the inward end of the cylindrical portion radially outwardly.
The annular seal lip (3) bonded to the outer annular member (4) is in elastic-contact with the axial outward side face (Y side face) of the annular flange portion (6B) of the inner annular member (6).
In a rolling bearing assembly having the oil seal assembly of this type as a sealing means, the inner and outer rings sometimes need to be separated from each other in order to disassemble the bearing assembly when the bearing assembly is inspected or receives maintenance. In such a case, if the rings are separated from each other in the axial direction with the oil seal assembly being assembled to the bearing assembly, the annular seal lip (3) bonded to the outer annular member (4) is squashed by the annular flange portion (6B) of the inner annular member (6) or the inner annular member (6) deforms because of reaction force from the outer annular member (4), resulting in impossible reuse of the oil seal assembly. In such a bearing assembly, in order to disassemble the bearing assembly without damaging the oil seal assembly, it is necessary to dismount the oil seal assembly from the bearing assembly before disassembling the bearing assembly, with the result that the disassembling of the bearing assembly requires an extra operation and time.